Writing instrument



FIG. 1 is a top plan view of a writing instrument embodying my invention;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a side elevational view thereof;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is a front perspective view thereof. 

The ornamental design for a writing instrument, as shown and described. 